Stringed musical instrument



April 18, 1950 R, M, SULLIVAN 2,504,752

STRINGED MUSICAL INSTRUMENT Filed April 15, 1948 FIGOU INVENTOR. ROY M.SULLIVAN ATTORNEY F is. e

Era-tented Apr.

. STRINGED MUSICAL INSTRUMENT RoyjM. Sullivan, Atlanta, Ga., assignor ofone halfto Horace W. Sullivan, Decatur, Ga.

Application April 15, 1948,-Serial'No. 21,220

7 Claims.

This invention relates to improvements in a stringed musical instrument,and particularly to aguitar capable ofv producing harmonious melody andchord accompaniment in unison, and wherein: only one finger is requiredfor fretting to produce all the chords,

I It is an object of my invention to provide a stringed musicalinstrument having four melody strings and strings for two open chordstuned in unison with the melody strings.

Another object of my invention is to provide a stringed musicalinstrument having'four melody strings and strings for two open chords,each with the proper bass members for playing and alternating the bass.

Another-object of my invention is to provide a stringedmus'icalinstrument having four melody strings, with strings for the major tonicchord .andproper bass member strings nextyand then -.-stringsforthedominant seventh chord and its proper bass members strung next, making atotal iof thirteen strings.

Another object of my invention is to provide :a stringed musicalinstrument in which tuning :inboth the major and seventh chords ischange- :able by tuning units operated other than by the hands of theoperator.

O' therand further objects and advantages of my'invntion will beapparent from'the following description taken in connection with theaccompanying'drawing in which like characters of reference designatecorresponding parts throughoutthe several'views, wherein: V

Fig. l'is atop-plan view of an instrument according tomy-invention. I

Fig. 2 is aside elevation of the instrument shown in Fig.1. h

Fig. 3 isa'n enlarged cross-sectional view showingdetails ef the controlmechanism.

Fig. 4 is a cross-sectional view taken along the line 4-4 in Fig. 3

Fig 5 is a detail view showing operation of a plunger.

Fig. 6 is a schematic detail viewillus'trating operation of a plunger. 7

Fig. 7 is an enlarged detail plan view of the bridge showing stringspacing.

'In the embodiment of theiinvention, herein described, 'thehollow'b'odyiu, which may be of conventional shape such as is used inthe construction of an ordinary guitar, is provided with an anchor plateII to which the strings are fastened, a primary bridge 12 over which thestrings pass, and a neck l3 which may be hollow and which terminates ina head l4 constructed toaccommodate conventional tuning devices IS. Theusual longitudinally spaced frets I5 are provided on the finger board. Asecondary bridge is shown at El, and an auxiliary bridge or string guideIt: may be employed to assist inmaintainproper alignment of the strings.In the playing position, the body If] is placed on the lap of theperformer and in order-that it may be convenientlyheld in a stationaryposition it is provided withhinged brackets l9, l9 which serve asabutments against each side of the right leg of the performer.

According to my inventiomthirteen strings are provided. Strings 2!), 2|,22 and 23 are the melody strings which are customarily tuned E, C sharp,A and E, in the'order named. The remaining nine strings 24, 25, 26, 21,28, 29, 30, SI and 32, which may be distinguished as chord acoompanimentstrings, are divided into four groups or sets which will be presentlydescribed. All of the strings are of course of appropriate gaugedependent upon the system of tuning employed by the performer.

Strung next to the melody strings is a group of three strings 2d, 25 and26 which may betuned normally as E, Csharp and A in the order named.Strung next to this'gro'up of three strings and associatedwith it is asingle string 21 which may be tuned A bass to provide the proper bassaccompaniment. I

Then follows another group of three strings 2'8, 29 and 30 which may betuned normally as D, G sharp and E in the order named. Strung next tothis group of three strings and associated with it is a group of twostrings 3i and 32 which'may be tuned. B bass and E bass, in the ordernamed, to provide the proper bass accompaniment.

Additionally, accordingto myinvention, means are provided'forautomatically changing the tuning in the major and seventh chords tominor and sixth tuning, respectively, at the will of the performer. Inorder to-accomplish this, movable plungers 33, 33 are provided understrings 25 and 28, respectively. The plungers 33, 33 are slotted attheir upperends as at 34, 34, respectively, to receive strings 25 and28, respectively, after they pass throughthe needle eye in: guide pins-35, 35', respectively. which are fixed to the head it. The plungers 33,33 extend through holes in the head I4 and are pivotally connected attheir lower ends to a system of pivoted links arranged to raise andlower the plungers. For example, plunger 33 is pivotally connected atits lower end with the upper end of a link 36 which is arranged tocooperate with a link 31 which is pivotally connected at its lower endto a fixed support 38. The lower end of link 36 and the upper end oflink 31 are pivotally connected together and to the end of slidable rod39, all as shown in Fig. 5. A similar set of links connects plunger 33'to slidable rod 39, as shown schematically in Fig. 6. Rods 39, 39' areslidably mounted for longitudinal movement within the hollow neck l3.Rigidly attached to the rods 39, 39 are operating members 40, 40,respectively, which are arranged to fit against opposite sides of theleft leg of the performer so that rod 39' can be pushed to the right,against the action of coil spring 4|, by pushing the left leg againstoperating member 40, and rod 39 can be pushed to the left, against theaction of coil spring 4|, by pushing the left leg against operatingmember 40'. Movement of rod 39 to the left is limited by brace member 42which is arranged to abut against operating member 40 when theassociated link system is extended to raise plunger 33. Movement of rod39 to the right is similarly limited by brace member 42 which isarranged to abut against operating member 40' when the associated linksystem is extended to raise plunger 33. Movement of rod 39 to the rightis adjustably limited by thumb screw 43 which is arranged to abut thestop plate 44 which is rigid- 1y attached to rod 39. Similarly, movementof rod 39' to the left is adjustably limited by thumb screw 43' which isarranged to about operating member 40'.

Movement of the operating members 40, 40' against the tension in springs4|, 4|, respectively, is selectively accomplished by pressure from theperformers knee, as explained above, to lower either plunger 33 or 33, adesired. Lowering the plunger 33 relieves some of the tension in stringso that by adjustment of thumb screw 43 this string may be tuned 0natural, with the plunger 33 lowered, and thus create minor tuning. Uponreleasing the pressure of the knee against operating member 40, theplunger 33 will again be raised by the action of spring 4i, and majortuning restored. Lowering of the plunger 33' relieves some of thetension in string 28 so that by adjustment of thumb screw 43 this stringmay be tuned D fiat, with the plunger 33 lowered, and thus create sixthtuning. Upon releasing the pressure of the knee against operating memberthe plunger, 33' will again be raised by the action of spring 4|, andseventh tuning restored.

According to my invention the major tuning can be changed automaticallyto minor tuning and the seventh tuning can be changed automtically tosixth tuning, all by means operated other than by the performers hands.The strings in both these chords are strung closely together, thusenabling the performer to fret the whole chord with the tip of onefinger or both chords with one finger, thus giving the performer freedomof the rest of his fingers for fingering the key board and carrying themelody and any other parts of the composition desired. With myarrangement of strings and the automatic tuning as described, all themajor, minor, sixth, and seventh chords can be made accurately while themelody is being played; and augmented fifths,

minor slxths and minor sevenths can be made by cooperation of the melodystrings as will be understood.

While I have illustrated and described a certain embodiment of myinvention, it will be understood that modifications, changes andadaptation may be made without departing from the scope of my inventionas defined in the appended claims.

I claim:

1. A stringed musical instrument having 13 strings comprising fourmelody strings and strings for two open chords tuned in unison with themelody strings.

2. A stringed musical instrument having 13 strings comprising fourmelody strings and strings for two open chords, each with the properbass members for playing and alternating the bass.

3. A stringed musical-instrument having four melody strings, strings forthe major tonic chord and proper bass member strings next, and thenstrings for the dominant seventh chord and its proper bass membersstrung next, making a total of thirteen strings.

4. A stringed musical instrument according to claim, 3 in which meansoperable other than by the performers hands are provided for changingthe tuning in both the major and seventh chords.

5. A stringed musical instrument according to claim 4 in which legoperable means are provided for selectively varying the tension in thesecond string of the major tonic chord and the first string of thedominant seventh chord groups.

6. A stringed musical instrument having a group of four melody stringsand nine other strings, said nine other strings being divided into fourgroups comprising a group of three strings which may be tuned normallyas E, C sharp and A in the order named, a group consisting of a singlestring which may be tuned A bass, said single string being strung nextto said group of three strings, a second group of three strings whichmay be tuned normally as D, G sharp and E in the order named, saidsecond group of three strings being strung next to said single string,and a group of two strings which may be tuned B bass and E bass, saidgroup of two strings being strung next to said second group of threestrings.

7. A stringed musical instrument according to claim 6 in which legoperable means are provided for changing the tension in the secondstring of said first mentioned group of three strings so as toautomatically change the tuning thereof from C sharp to C natural andback again at will, and for selectively changing the tension in thefirst string of the second group of three strings from D to D fiat andback again at will.

ROY M. SULLIVAN.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS

